Diazotizable azo dyestuffs



Patented Jan. 14, 1941 UNITED STATES DIAZOTIZABLE AZO DYESTUFFS Fritz,Suckfiill, Leverkusen-Wiesdorf, and Heinrich Clingestein,Cologne-on-the-Rhine, Germany, assignors to General Aniline & FilmCorporation, a corporation of Delaware No Drawing. Application March 9,1938, Serial No. 194,832. In Germany March 3, 1937 g 9 Claims. (01.8-46) The present invention relates to new diazotizable azo dyestuffs,to a method of preparing the same, to a process of dyeing and to dyedfibers; more particularly it relates to diazotizable yellow azodyestuffs which may be represented by the general formula:

In this formula A--N=N stands for the radical of a diazo compound whichmay contain one or several azo groups and also free hydroxy groups,being suitable for the formation of yellow azo dyestuffs and'being freefrom diazotizable amino groups, B, stands for an arylene radical and Ystands for a negativating substituent.

Our new dyestufis are obtainable by causing yellow azo dyestuffs of theformula:

wherein A and B mean the same as stated above to react with an aroylhalide containing in the aryl nucleus besides a substituent beingconvertible into the amino group, such as a nitro group or an acylarninogroup, a negativating substituent and converting the said convertiblesubstituent into the amino group, for instance by reduction or saponifcation.

Suitable aroyl halides for our process are halides of the followingformula:

g C O.halogen wherein X stands for a substituent being convertible intothe amino group such as a nitro group or an acylamino group and Y standsfor a negativating substituent, as, for instance, CN, SO2-, CO-, -NO2,or halogen; the divalent sub-stituents SO2 and --CO have one bondattached to the aryl nucleus, while the other bond may carry anyradical. Such halides are, for instance, cyanonitrobenzoyl chlorides,monoor dihalogen-nitro-benzoyl chlorides, dinitrobenzoyl chlorides, theacid chlorides of nitrophenylalkylsulfone carboxylic acids and so on.

Our new dyestuffs shown in contrast to the known dyestuffs, which do notcontain the negativating substituent in the amino aroyl radical theadvantage, when diazotized on the fibre and developed with B-naphthol,of yielding yellower shades. The diazotizable dyestuifs used until nowfor yellow shades had to be developed with pyrazolones in order toobtain the yellow shade, for, when developed with fl-naphthol, thesedyestufls yield red to orange shades. The technical advantage of thepresent dyestuffs become chiefly evident in shading, as in the dyeingpractice mostly not the pure diazotizable dyestuffs but mixtures of thesame'are used, in order to obtain different shadesin-differentdirections, such as fashion shades and so on. Although most of thediazotizable dyestuils are developed with li-naphthol a yellow-shadingwas not possible with dyestuffs of the fi-naphthol series up to thepresent. The known yellow diazotizable dyestuffs had, without exception,to be developed with pyrazolone as already mentioned above, andtherefore they were not suitable for shading in the ,B-naphthol series-.Only such a diazotizable dyestuif can be suitable for this purpose whichyields develope'd'with ,B-naphthol yellow shades, since it ispractically not possible to develop either successively orsimultaneously with B-naphthol and pyrazolone. In some cases it waspossible to shade with orange instead of yellow, however, the reddishtinge shown by the dyeings thus produced mostly. proved veryundesirable. Owing to this quite a number of shades wanted could not beobtained. In the dyeing practice therefore the ardent want existed fordiazotizable dyestuffs which can be developed to yellower shades withfi-naphthol and with which yellow-shading can be carried out withoutdifiiculties. For the first time diazotizable dyestuffs of this kind aredisclosed by the present invention; they meet a long felt want andtherefore represent a remarkable 2 and important advance in the, art.

The following examples illustrate the invention, without howeverrestricting it thereto, the parts being by weight:

Example 1 303 parts of 2-naphthylamino-6.8-disulionic acid arediazotized with 69 parts of sodium nitrite, 110 parts ofm-toluidine--dissolved in hydrochloric acidare added to the diazocompound. When the couplingis complete, the dyestuff is isolated byadding acid until the liquid shows a reaction acid to Congo red,dissolved in water with sodium carbonate to a neutral solution, and thentreated at Gil- C. with 200 parts of p-nitrobenzoyl chloride and an.acid binding agent.

After the completed condensation the nitrobenzoylated dyestuif isdissolved in water and reduced at 60 C. with 420 parts of crystallizedsodium sulfide. The reduced dyestuff is dissolved in water to a neutralsolution and parts of sodium nitrite and then 500 parts of hydrochloricacid (19.5 B.) are added. After the excess of nitrous acid has beenremoved, a solution of parts of m-toluidine in hydrochloric acid isadded to the diazo compound and coupling is completed by adding sodiumacetate.

The aminodisazo dyestuff is isolated by adding acid until the liquidshows a reaction acid to Congo red, dissolved in Water to a neutralsolution and treated with the chloride of l-carboxyof crystallizedsodium sulfide.

2-nitrophenylmethylsulfone of the following constitution:

in the presence of an acid binding agent, until the amino group can nolonger be detected by diazotizing. After the condensation is completethe dyestuff is isolated, again dissolved and reduced at 75 C. with 420parts of crystallized sodium m-toluidine and an excess of sodiumacetate. After the coupling is complete, the mixture is treated with thechloride of 4-carboxy-2-nitrophenylmethyl sulfone until the amino groupcan no longer be detected by diazotizing. The

1 reduction of the nitro group is effected with 420 parts ofcrystallized sodium sulfide in an aqueous solution at 75 C. The completedyestuff is separated by adding-salt, isolated and dried. It correspondsin its free state to the following formula:

OOOH

sulfide. The isolation of the complete dyestufi is effected by addingsalt. The dyestufl' which corresponds in its free state to the followingformula:

dyes cotton after diazotization and developing with s-naphtholessentially yellower shades than the corresponding dyestuif which doesnot contain the methyl sulfone radical.

Example 2 230 parts of 4-aminoacetanilide-3-sulfonic acid are dissolvedin water with sodium carbonate to a neutral solution, 320 parts ofhydrochloric acid isolation the dyestuff is treated at 75 C. in thepresence of an acid-binding agent, with p-nitrobenzoyl-chloride, untilthe amino group can no longer be detected by diazotising.

530 parts of the dyestuff thus obtained of the following constitution:

NaOOC S Na are reduced in water at 60-65 C. with 420 parts The isolatedreduction product is dissolved in water, further diazotized with 75parts of sodium nitrite and 500 parts of hydrochloric acid (19.5 B.) andthe diazo solution is united with 110 parts of S OaH and dyes cottonafter diazotization and developing with p-naphthol essentially yellowershades than the corresponding dyestuif which does not contain themethylsulfone group.

Example 3 On substituting in Example 2 3.5-dinitrobenzoylchloride forthe chloride of the 4-carboxy-2- nitrophenylmethylsulfone and treatingthe dinitrobenzoyl dyestuff with 420 parts of crystallized sodiumsulfide at 75 C. until one nitro group is reduced to the amino group, adyestufi is obtained which corresponds in its free state to thefollowing formula:

| CH5 NH:

and which, when dyed on the fiber, diazotized and developed withp-naphthol, yields distinctly yellower shades than the correspondingreduced dyestuff prepared from 3-nitrobenzoyl-chloride, which onlydiffers from the first dyestufi by the absence of the nitro group.

We claim: 7

1. As new products the diazotizable yellow azo dyestuffs of the generalformula wherein AN=N stands for the radical of a diazo compound beingsuitable for the formation of yellow azo dyestuffs and being free fromdiazotizable amino groups, B stands for an arylene radical of thebenzene series and Y stands for a negativating substituent selected fromthe group consisting of CN, NO2, halogen, --SO2, and --CO the freevalences of the S02 and CO groups being connected to an organic radical.

2. As new product the diazotizable yellow azo .dyestuff whichcorresponds in its free state to the following formula:

N=NQNEL o 001v: QNELC oQs 01cm CH: OH; I NH:

3. As new product the diazotizable yellow azo dyestufi which correspondsin its free state to the following formula:

COOH

10 4. The process cellulosic fibres a SOsH which comprises applying todiazotizable yellow dyestufi of the general formula wherein AN=N- standsfor the radical of a diazo compound being suitable for the formation ofyellow azo dyestuffs and being free from diazo- 20 tizable amino groups,B stands for an arylene radical of the benzene series and Y stands for anegativating substituent selected from the group consisting of -CN,-NO2, halogen, SO2, and

C'O the free valences of the S02 and CO 2 groups being connected to anorganic radical,

diazotizing and coupling with c-naphthol.

5. The process which comprises applying to cellulosic fibers thediazotizable yellow azo dyestutf which corresponds in its free state tothe 30 following formula N=N-Q NHlC OON= QNILC OQ-S 0,011: r 30 CH: CH:NH:

HOaS

diazotizing and coupling with p-naphthol.

6. The process which comprises applying to 40 cellulosic fibers thediazotizable yellow azo dyestufi which corresponds in its free state tothe following formula diazotizing and coupling with p-naphthol. 5O '7.Cellulosic fibers dyed according toa process as claimed in claim 4.

8. Cellulosic fibers dyed according to a process as claimed in claim 5.

9. Cellulosic fibers dyed according to a process 55 as claimed in claim6.

FRITZ sUcKFt'im. HEINRICH CLINGESTEIN.

